Low concentrations of the lathrogen beta aminopropionitrile (BAPN, 0.01 to 0.1mM) stimulated (up to 130 percent) collagen and noncollagen protein synthesis by WI-38, 3T3 and primary cultures of chick embryo fibroblasts. The stimulation is not due to increased isotope uptake because the specific activity of radioactive proline in the treated cells was the same as control cultures. Higher concentrations of BAPN (1 to 5mM) caused a selective reduction of collagen synthesis by 3T3 and WI-38 cells and were toxic to primary chick embryo fibroblasts. Future studies will determine if the selective reduction of net collagen synthesis by cultured cells treated with BAPN (1 to 5mM) is due to increased susceptibility of the uncrossed-linked collagen to collagenase (or general proteases). This information would further support the clinical use of BAPN in preventing excessive scar formation. In other studies, chick embryo frontal bones were treated with triamcinolone (0.2 to 20 mg/ml) in culture and then analyzed for changes in collagen metabolism. The results of these studies showed that triamcinolone had no effect on collagen synthesis. This observation is contrary to the hypothesis that steroids inhibit wound healing by specifically blocking collagen synthesis. However, our present findings substantiate our previous observations that triamcinolone-treated keloids resorb in the absence of a reduction of collagen synthesis. Our current findings have led us to concentrate our attention on other possible mechanisms for steroid interference with the healing process e.g. enhancement of collagenase activity. We will continue our studies to determine if intralesional triamcinolone causes a reduction of serum alpha-globulins in keloids thus resulting in increased collagenase activity. Future studies are also planned to study the interaction of macrophages with fibroblasts to enhance fibroplasia and collagen synthesis. BIBLIOGRAPHIC REFERENCES: Diegelmann, R.F., Cohen, I.K., Rothkopf, L.C.: Measurement collagen biosynthesis during wound healing. Journal of Sergical Research, 19, October, 1975. Cohen, I.K., Theogaraj, S.D.: Nasolabial Flap Reconstruction of the floor of the mouth after extirpation of oral cancer. The American Journal of Surgery, (In Press), July, 1975.